v0.15.1 - Error Propagation Milestone

Error Propagation Milestone

This release marks a significant milestone: the @error(code) metafunction is now fully working!

Key Features

• @error(code) metafunction - Sets CY flag and returns with error code
• Proper Z80 code generation - Generates SCF (Set Carry Flag) instruction
• CY flag + A register ABI - Complete error handling ABI

Example

enum FileError { None, NotFound, Permission }

fun read_file?(path: u8) -> u8 ? FileError {
    if path == 0 {
        @error(1);  // FileError.NotFound - sets CY flag
    }
    return path;
}

Generated Z80 Assembly

LD A, D          ; Load error code
SCF              ; Set carry flag (error indicator)
RET              ; Return with error

Metrics

• Compilation rate: 81% (48/59 examples)
• No regressions from previous release

Documentation

• Error Propagation Milestone Report
• Claims Verification Report

What's Next

• Enum value access (ErrorType.Value syntax)
• ?? @error propagation syntax cleanup
• Type inference for ?-suffixed function calls

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Full Changelog: v0.9.7...v0.15.1